There are two bags going into the same line. Sometimes the feeding won't drip causing an error message. One bag is for water, the other is for the product. I'm used to using the older pumps where there was only one bag. We used to "pull" on the line until it dripped. I think there is air in the line causing the product not to drip. The client using this at home, states that sometimes they go thru 2-3 setups before the bags will drip

Health & Beauty - Kendall - KANGAROO Pump Sets